Burglar-alarm.



lJNrTEn %TATES %PATENT OFFICE.

RICHARD LEHMAN, OF NEW YORK, N. Y.

BuRGLAR ALARM.

SPECIFIGA'ECN forming part of Letters Patent No. 686,093, datecl November 5, 1901. Application filed March 6,1901. Serial No. 50,070. (Ne model.)

To all whom it' may conccrn: i

Beit known that I, RICHARDLEHMAN, a citizen of the Empire of Germany, residing in New York, borough of Bronx, in the State of New York, have invented, certain new and useful Improvements in Burglar-Alarms, of which the following is a specification.

This invention relates to certain improvements in bnrglar-alarms ot' that class which are set in an inclined position between the door and the floor so as to give an alarm when an attempt to open the door is made; and the invention consists of a burglar-alarm comprising a main frame provided at its lower end with means for engaging the floor, a clocktrain supported on said main frame and having a suitable casing, an alarm-bell operated by said clock-train, a slide-frame having at its upper end two heads located in the same horizontal plane,nea1s for guiding said slidef rame in said casing, means for arresting m'otion of the slide-frame, neans interposed be tween the slide-frame and clock-train for releasing the lat-ter by the notion of the slideframe, and a socket-plate attached to the door and provided with two sockets or recesses located in one horizontal plane and at the same distance apart as the heads of the slide-frame, said recesses or heads being so formed as to permit detachment of the slideframe from the socket-plate when the main frame is raised from the floor, but to interlock when engaging the floor.

In the accompanying drawings, Figure 1 represents a perspective View of my improved burglar alarm, showing it in position for use. Fig. 2 is a vertical longitudinalsection drawn on a larger scale. Fg. 3 is a front View of the same, partly in section; and Fig. 4 is a detail horizontal section through the clocktrain, showing the slide-frame and the means for starting the clock-train by the same.

Similar letters of reference indicate corresponding parts.

Referring to the drawings, A represents a main frame, which is composed of parallel pieces a, a, that are connected by transverse brace-pins a'. To the middle part of the main frame is applied the boX-shaped casing B of a clock-train B', which is wound up by akey in the usual manner and so arranged that an alarm-bell B is sounded when the escapement ot' the clock-train is released. On the upper end of the nain t'rame A is guided in the box B of the clock-train an auxiliary slide-frane O, the sides d ot' which are Stiftened by a transverse pin or rods d'. The slide-frame C is provided at its upper ends with T-shaped heads (1 at a snitableinclination, so as to permit their insertion into the recesses of a metallic socket-plate D, that is attaehed to the door by screws or otherwise. The soekets may be made into the form of mortices cut in the door; but it is preferable to use a metallic socket-plate that is screwed onto the door, so as to prevent injuring or defacing the door. The lower pointed ends of the side pieces a of the main frame A are `inserted into recesses of the floor and a recessed retaining-plate E, which is screwed to the floor. When' a carpet or other' floor-covering is used, itis preferable to dispense with the recesses in the floor and the recessed plate E and insert the lower ends directly into the carpet or floor-covering when the burglar-alarm is placed in position for use.

To one of the transverse rods d' of the slideframe C is pivoted a link f, the opposite end of which is pivoted to a fulcrumed lever f' at the interior of the casing of the clock-train B', the opposite end of the fulcrumed'lever being connected with an arm f on the arbor of the escapement g', as shown in Fig. 4.

The lower ends of the side pieces d of the auxiliary franie C are provided with studpins h, which are guided in slots h' ot the side walls of the casing, so as to limit the motion of the sliderame C in connection with stopblocks 71 on the side walls of the casing. This downward motion of the slide-frame C produoes the release of the escapement by the action of the intermediate levers, so that the clock-train is started, the hammer of the alarm-bell operated, and the latter sounded.

When my improved alarm is placed in position for use, as shown in Fig. 1, its upper end is inserted into the socket-plate attached to the door, while the lower end engages the floor or carpet. 'The slide-france is in extended position, so as to place the escapement ingear with the escapement-wheel and hold thereby the clock-train in position of rest'. As soon as an attempt is made to open the door the auxiliary frame is moved in downward IOO direction, so as to release the escapement by the lever mechanisn described and produce thereby the ringing of the bell, which is continued until the slide-frame is raised again and the escapement set into engagement with the esoapenent-wheel.

I am aware that burglar-alarms of similar construction have been patented heretofore. In most of these constructions the upper pointed ends of the alarm scrateh the door or otherwise injure the same when setting the alarm in position for use. At the same time such an alarm can be made inoperative by slight and repeated motion imparted to the door before fully opening the same, so that the ends are released from the door and the alarm dropped to the floor without ringing the bell. This disadvantage is avoided in my Construction by the use of the socketplate, into which the upper T-shaped heads of the slide-frame are inserted, so that the alarm cannot be detached o'r liberated froni the door by shaking or otherwise moving the door from the outside, but can only be disengaged by raising the main frame from the floor and swinging the device in upward direction. When the alarm is not required for use, the heads of the slide-frame are detached from the socket -plate and the entire alarm device hung up on a hook alongside of the door, to be taken off from the hook and placed in position whenever required for use.

&56,093

Having thus described my invention, 1 claim as new and c'lesire to secure by Letters Patent- A burglar-alarm, consisting of a main frame provided at its lower end with means for engaging the floor, a clock-train supported on main frame and having a casing, an alarmbell operated by said clocktrain, a slideframe having at its upper end two heads located in one horizontal plane, means for guiding the slide-frame in said casing, means for arresting the motion of the slide-frame,means interposed between the slide-f rame and clocktrain for releasing the latter by the motion of the slide-frame, and a sooket-plate attached to the door and provided with two sockets or recesses located in one horizontal plane and at the same distance apart as the heads of the slide-frame, said recesses and heads being so formed as to pernit detachment of the slideframe from the socket-plate when the main frame is raised from the floor, but to interlock and prevent detachment when engaging the floor, substantially as set forth.

In testimony that I claim the foregoing as my invention I have signed my name in preseuce of two subscribing witnesses.

RICHARD LEHM AN.

Witnesses:

PAUL GOEPEL, GEORGE GEIBEL. 

